Sunday, November 28, 2010

Phenlylalanine: Key to Healthier Food?

Scientists at Purdue University have found the last undiscovered gene responsible for making of the amino acid phenylalanine. This discovery could lead to controlling this amino acid to raise plants nutritional values and produce better biofuel feedstocks.

Phenylalanine is an amino acid essential in the body of humans, but humans must get it from food they eat (mainly plants). In plants, phenylalanine is important for plant protein synthesis, production of flower scent, anti-oxidants and lignin. Lignin is the principal component in a plant cell wall to help keep the plant stand up and also acts as a barrier in the production of cellulosic ethanol. Cellulosic ethanol is a biofuel produced from wood, grasses and the non-edible parts of plants.

If scientists were able to decrease the amount of phenylalanine in plants, that would lead to a reduction of lignin, which would improve the digestibility of materials originally blocked by the amino acid, creating more biofuel to be easily digested. If scientists could increase phenylalanine in plants, it could potentially boost the nutritional value in some foods. This is because it would increase the amount of anti-oxidents produced in plants (by phenylalanine), which when digested by humans, would have an increased amount of nutritional value.

Finding this gene is important, because now they have all the components needed to replicate this amino acid, hopefully being able to change the amount of phenylalanine in plants, increasing or decreasing depending on the desired function (biofuel or nutrition)


Do Fish Feel Pain?

Do fish feel pain? Pain like humans do? Study done in April of 2009 says they do.

In this study, there were two groups of fish, one injected with morphine, a pain reliever, and the other with a placebo, saline, which is a kind of medicine used to relieve physical pains psychologically (a fake pain killer). After injected, they were treated to a burning sensation, which would not damage any tissue. Both groups of fish wriggled as a response to the burning. However, after time, the fish with morphine went on their day unaffected, while the fish that had gotten saline were weary.

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This shows that fish feel pain because the fish with the painkillers were unaffected and went on the day as if nothing happened, while the fish with the fake painkillers were obviously affected.

From this study, scientists begin to think that fish do feel pain like humans, as previously thought that they do not.

For more information on this study go to:

Sunday, November 7, 2010

Osmoregulation in Sharks

"Osmoregulation is the control of the levels of water and mineral salts in the blood." (Link). Osmoregulation relates to homeostasis, which is where cells have the correct amount of water, mineral salts, glucose and temperature. In every organism, they are trying to create a perfect homeostatic environment, where they can live and thrive as a healthy living thing. Each different organism must do different things to create this homeostatic environment. Sharks are included in these organisms.

Sharks are special because their blood is naturally isotonic to where is lives. This means that the number of solutes inside is equal to the water around the shark. Because of this, sharks are considered osmoconformers, the opposite of osmoregulators. This is usual for marine organisms.

Sharks are able to achieve this isotonic state because of the high concentration of urea and trimethylamine N-oxide (TMAO) in them. Because of this concentration, most sharks are not able to survive in freshwater environments. An exception to this rule, however is the the Bull Shark. In sharks, their kidneys are used to release the salt into the ocean, and determine how much. If a shark were placed in a freshwater environment, their kidney would not be able to adapt to the change in saltiness, causing the shark to die because they can't keep an isotonic state of living. Bull Sharks are different because in a gradual change from ocean to freshwater (example: migrating), their kidneys are able to adapt to these changes, and keep an isotonic state.